Brajkovic Dragan, Ducharme Michel B
Human Protection and Performance Group, Defence Research and Development Canada-Toronto, Ontario, Canada M3M 3B9.
J Appl Physiol (1985). 2003 Aug;95(2):758-70. doi: 10.1152/japplphysiol.00051.2003. Epub 2003 May 2.
The primary purpose of the present study was to compare the effectiveness of two forms of hand heating and to discuss specific trends that relate finger dexterity performance to variables such as finger skin temperature (T(fing)), finger blood flow (Q(fing)), forearm skin temperature (T(fsk)), forearm muscle temperature (Tfmus), mean weighted body skin temperature (Tsk), and change in body heat content (DeltaH(b)). These variables along with rate of body heat storage, toe skin temperature, and change in rectal temperature were measured during direct and indirect hand heating. Direct hand heating involved the use of electrically heated gloves to keep the fingers warm (heated gloves condition), whereas indirect hand heating involved warming the fingers indirectly by actively heating the torso with an electrically heated vest (heated vest condition). Seven men (age 35.6 +/- 5.6 yr) were subjected to each method of hand heating while they sat in a chair for 3 h during exposure to -25 degrees C air. Q(fing) was significantly (P < 0.05) higher during the heated vest condition compared with the heated gloves condition (234 +/- 28 and 33 +/- 4 perfusion units, respectively), despite a similar T(fing) (which ranged between 28 and 35 degrees C during the 3-h exposure). Despite the difference in Q(fing), there was no significant difference in finger dexterity performance. Therefore, finger dexterity can be maintained with direct hand heating despite a low Q(fing). DeltaH(b), Tsk, and T(fmus) reached a low of -472 +/- 18 kJ, 28.5 +/- 0.3 degrees C, and 29.8 +/- 0.5 degrees C, respectively, during the heated gloves condition, but the values were not low enough to affect finger dexterity.
本研究的主要目的是比较两种手部加热方式的效果，并探讨将手指灵活性表现与诸如手指皮肤温度（T(fing)）、手指血流量（Q(fing)）、前臂皮肤温度（T(fsk)）、前臂肌肉温度（T(fmus)）、平均加权体皮肤温度（T(sk)）以及体热含量变化（ΔH(b)）等变量相关的具体趋势。在直接和间接手部加热过程中测量了这些变量以及体热储存率、脚趾皮肤温度和直肠温度变化。直接手部加热是使用电加热手套来保持手指温暖（加热手套条件），而间接手部加热是通过用电加热背心主动加热躯干来间接温暖手指（加热背心条件）。七名男性（年龄35.6±5.6岁）在-25℃空气中坐在椅子上3小时期间接受了每种手部加热方法。与加热手套条件相比，加热背心条件下的Q(fing)显著更高（P<0.05）（分别为234±28和33±4灌注单位），尽管T(fing)相似（在3小时暴露期间范围为28至35℃）。尽管Q(fing)存在差异，但手指灵活性表现没有显著差异。因此，尽管Q(fing)较低，直接手部加热仍可维持手指灵活性。在加热手套条件下，ΔH(b)、T(sk)和T(fmus)分别降至-472±18kJ、28.5±0.3℃和29.8±0.5℃，但这些值不足以影响手指灵活性。
